Spectrum: the Lockwood Thompson Dialogues is a new program created for the Cleveland Public Library by Cleveland Public Art.   The topic for the 2006 series is Cultural & Creative Migrations.  The April event will bring internationally acclaimed artist Shahzia Sikander together with moderator Kurt Andersen, host and co-creator of Public Radio International’s Studio 360, to discuss topics as diverse as cultural identity and the relationship of technology and globalization to the act of creating art.